Mailshake has been around a long time, and it earned its reputation as one of the simplest ways to get a cold email sequence out the door: mail merge, automated follow-ups, and an editor built for people who have never run outbound before. Lead finding is not native to the core product — it is a paid Data Finder add-on layered on top of a tool that was built for sending to lists you already have, and AI in Mailshake mostly means generating copy variations, not researching each prospect.
Defrost is built around a different question: instead of asking you to bring a list and a sequence, it runs the whole pipeline — finding leads independently in real time through search, scraping, and public registries, verifying every address through a multi-provider verification cascade, writing personalized copy per recipient, and sending through a Defrost-managed relay with per-customer DKIM and enforced safety limits. There is a done-for-you tier if you would rather not run any of it yourself; Mailshake has no equivalent.
| Feature | Defrost | Mailshake |
|---|---|---|
| What it fundamentally is | A done-for-you cold outreach pipeline: find leads → verify → write → send. | A sales engagement / sequence tool for sending mail-merge campaigns to lists you already have, with a phone dialer and paid data add-ons. |
| Lead sourcing | Independent, live discovery per campaign via search, scraping, and public registries. No shared database, no data-broker credits to buy. | Not native to sending — you upload your own contacts, or buy credits for the separate Data Finder add-on ($19/mo, or a free credit allotment bundled into paid plans) to filter prospects by role, location, and company. |
| Email verification | Every address checked through a multi-provider cascade before sending. | "Unlimited email verification" is included on paid plans for cleaning lists you supply; Data Finder results are a separate purchased pool. |
| Email writing | Per-recipient personalized copy generated as part of the pipeline for every lead. | Mail merge fields plus SHAKEspeare AI, which generates or randomizes copy variations for A/B testing rather than researching each individual prospect. |
| Sending infrastructure | Defrost-managed relay with per-customer DKIM, automated warmup, and a 3% bounce-rate auto-pause. | Send from your own connected Gmail/Outlook mailboxes, with a free SMTP warmup tool, a domain setup assistant, and an in-app spam-word checker. |
| Pricing model | Flat monthly plans from $79/mo (500 leads, 2 mailboxes) to $1,200/mo (10,000 leads, 40 mailboxes). | Per-mailbox plans from $29/mo (Starter, 1 email address, 1,500 sends/mo) to $99/mo (Sales Engagement, 10 email addresses, unlimited sends, phone dialer), plus a custom-priced Agency plan; Data Finder and extra mailboxes are separate add-ons. |
| Trial | No free tier — card charged at checkout, plan active immediately, backed by a 30-day money-back guarantee. | No free trial — payment required upfront, cancellable anytime before renewal. |
| Done-for-you option | Yes — a DFY tier where Defrost runs the whole campaign for you. | None advertised — the product is self-serve, including its phone dialer and social-outreach features. |
| Who runs it day to day | Anyone — describe your ideal customer once, Defrost handles sourcing, verification, copy, and sending. | Best for reps and small teams who already have a list (or budget for credits) and want a simple, low-cost way to run mail-merge sequences and calls themselves. |
Who should choose Defrost
Choose Defrost if you want the outreach outcome — real, current leads that are verified and personalized before they ever hit a mailbox — without stitching together a list source, a data-credit add-on, and a separate sending tool. It suits founders, SMBs, and sales teams who would rather describe their ideal customer once and let the pipeline run than manage list quality by hand. If you have ever imported a purchased or scraped list into a tool like Mailshake and watched bounces pile up, see our breakdown of why bought lead lists bounce and the fuller cold email deliverability guide.
Who should choose Mailshake
Choose Mailshake if you already have a list — your own contacts, a CRM export, or leads from another source — and mainly need an affordable, easy-to-learn tool to mail-merge, sequence follow-ups, and layer in phone or social touches yourself. Its low entry price, simple editor, and optional Data Finder credits make it a reasonable fit for reps who want to own the process end to end rather than hand it off.
Sources
Frequently asked questions
- Does Defrost include lead sourcing, unlike Mailshake's base plan?
- Yes. Mailshake is built for sending to lists you already have — lead sourcing is a separate paid Data Finder add-on. Defrost sources leads independently for every campaign through live search, scraping, and public registries, then verifies each address through a multi-provider cascade, all included in the plan.
- Can I move my existing Mailshake contact list and sequences to Defrost?
- Defrost doesn't import Mailshake sequences directly — it builds fresh campaigns from your ideal customer profile rather than an uploaded list. If you have people who replied or unsubscribed in Mailshake, export that list and import it as a suppression CSV before your first Defrost campaign sends.
- Who writes the emails — is it like Mailshake's SHAKEspeare AI?
- Different job entirely. SHAKEspeare generates or randomizes copy variations for A/B testing within sequences you still write. Defrost generates personalized, per-recipient copy for every lead automatically as part of the pipeline, so there is no template to draft or variant to test yourself.
- Is there a done-for-you plan, since Mailshake doesn't offer one?
- Yes — Defrost has a DFY tier where Defrost runs the whole campaign for you, sourcing, verifying, writing, and sending on your behalf. Mailshake has no managed equivalent; every feature, including its phone dialer and social outreach, is self-serve.